Integrated Solar Combined Cycle Plant Research Articles

Recent Developments in Integrated Solar Combined Cycle Power Plants

Global concern for depleting fossil fuel reserves have been compelling for evolving power generation options using renewable energy sources. The solar energy happens to be a potential source for running the power plants among renewable energy sources. Integrated Solar Combined Cycle (ISCC) power plants have gained popularity among the thermal power plants. Traditional ISCC power plants use Direct Steam Generation (DSG) approach. However, with the DSG method, the ISCC plant’s overall thermal efficiency does not increase significantly due to variations in the availability of solar energy. Thermal Energy Storage (TES) systems when integrated into the solar cycle can address such issues related to energy efficiency, process flexibility, reducing intermittency during non-solar hours. This review work focuses and discusses the developments in various components of the ISCC system including its major cycles and related parameters. The main focus is on CSP technologies, Heat Transfer Fluid (HTF), and Phase Change Material (PCM) used for thermal energy storage. Further, study includes heat enhancement methods with HTF and latent heat storage system. This study will be beneficial to the power plant professionals intending to modify the solar-based Combined Cycle Power Plant (CCPP) and to retrofit the existing Natural Gas Combined Cycle (NGCC) plant with the advanced solar cycle.

Thermal performance analysis of a concentrated solar power system (CSP) integrated with natural gas combined cycle (NGCC) power plant

In this study, a concentrated solar thermal power plant (CSP) with parabolic trough collectors integrated into a reference triple-pressure NGCC power plant as an Integrated Solar Combined Cycle (ISCC). The aim is to study and assessment the overall performance of different hybrid schemes of ISCC plants. Thus, A detailed thermodynamic model of the proposed ISCC plants has been developed to investigate the thermodynamic impact of solar heat rate injected in the high and intermediate pressure sections (HP, IP) of the NGCC plant at different seasons of the year. The cycles have been characterized and simulated under southern Egypt climate. An increase in the NGCC output power of 52.315 MWe with peak net thermal efficiency of 64.86% and solar to electric conservation efficiency of 46.95% are obtained from the integration process in the HP section. The increase in power output reaches a limit of 43.38 MWe with a net efficiency of 63.82% and solar to electric efficiency of 38.85% for integration in the IP section. The results of the analysis have been indicated that the higher the solar energy injected the higher is the solar electricity production and the higher is the overall thermal efficiency.

Integrated solar thermal combined cycle for power generation in Iraq

Solar thermal power has already shown enormous promise as a source for power generation. With limited environmental impacts and an immense abundance, it offers a reasonable prospect to the sunny countries such as Iraq, that enables the country to lead the development of industrial-scale solar power generation in the region. However, the electricity distribution systems would be confronted by daily and annual variance of solar irradiation. To compensate for this variance the integrated solar combined cycle (ISCC) with a natural gas power plant is the solution. This study investigates the potential of ISCC power plants in Iraq in which preferred technologies and economic feasibility are analysed. The analysis shows it is the best interest of Iraq to invest in at least one large-scale ISCC power plant among the future planned power plants. The most promising location for such a plant would be in Al Anbar, the immense western desert in Iraq, yet other six locations for such power plants have potential as well. The economic analysis showed a high capital cost for the concentrated solar power (CSP) plant compared to the natural gas (NG) plant, as the CSP formed 67% of the total capital investment, though, the operating and maintenance cost of CSP formed only about 5% of the total ISCC plant cost at $1,688,281 per year, and the direct operating and maintenance cost of CSP and NG plants were 34, and 164 $.kW−1, respectively.

EVALUATION OF THE PERFORMANCE AND ENERGY EFFICIENCY OF INTEGRATED SOLAR COMBINED CYCLE POWER PLANT

Abstract: An integrated solar combined cycle (ISCC) composed of a triple-pressure natural gas combined cycle and parabolic trough collector solar field is investigated in this paper. The purpose is to study and evaluate the performance of the cycle when the solar heat injected into the heat recovery steam generator of the steam cycle. Thus, a thermodynamic model of the proposed ISCC plant has been developed in Mathcad environment to simulate and analyze the cycle performance ate different seasons of the year. It has been found that the solar energy can generate steam that can be used to increase the power output of the steam cycle from 182 MWe to 237 MWe with an increase of 30% from reverence value. This can achieve an annual reduction in CO2 emission of 75000 tons/year.

Performance assessment of an integrated solar combined cycle in the southern of Algeria

Among all the hybrid solar thermal technologies available up to now, the Integrated Solar Combined Cycle (ISCC) is nowadays the most efficient system for converting solar energy into electricity. This power plant is a combination of a parabolic trough solar field with a conventional combined cycle. In the present article, the performance of an ISCC plant under southern Algerian climate has been investigated. To do so, a thermodynamic model has been developed to evaluate solar radiation intensity as well as the overall performance of the hybrid solar power plant.The analysis has shown that solar to electricity efficiency could reach up to 14.4% during sunny periods. Furthermore, an overall thermal efficiency of about 60% is feasible. It has also been found that the amount of electricity produced increases with several operation parameters such as the time of the day, the mass flow rate of the heat transfer fluid and the angle of incidence on the collector surface.

Dynamic simulator and model predictive control of an integrated solar combined cycle plant

This paper presents the design and evaluation of a dynamic simulator for an ISCC (integrated solar combined cycle) plant. The design of the simulator is based on the phenomenological equations for both a combined cycle plant and a solar plant. The simulator incorporates a regulatory control strategy based on PI (proportional-integral) controllers and was developed in the MATLAB/Simulink® environment. A MPC (model predictive control) strategy established at a supervisory level is presented. The intent of the strategy is to regulate the steam pressure of the superheater of the ISCC plant. The combined use of the simulator and the supervisory control strategy allows for the quantification of the reduction in fuel consumption that can be achieved when integrated solar collectors are used in a combined cycle plant. The ISCC plant simulator is suitable for designing, evaluating and testing control strategies and for planning the integration of solar and combined cycle plants.

Thermodynamic evaluation of solar integration into a natural gas combined cycle power plant

The term integrated solar combined-cycle (ISCC) has been used to define the combination of solar thermal energy into a natural gas combined-cycle (NGCC) power plant. Based on a detailed thermodynamic cycle model for a reference ISCC plant, the impact of solar addition is thoroughly evaluated for a wide range of input parameters such as solar thermal input and ambient temperature. It is shown that solar hybridization into an NGCC plant may give rise to a substantial benefit from a thermodynamic point of view. The work here also indicates that a significant solar contribution may be achieved in an ISCC plant, thus implying substantial fuel savings and environmental benefits.

A Study on Solar Multiple for an Integrated Solar Combined Cycle System with Direct Steam Generation

This paper presents a study on optimizing the solar multiple for integrated solar combined cycle (ISCC) systems with direct steam generation (DSG). ISCC systems with different solar multiple values are studied, for which the performance is characterized under design-point and annual conditions. Based on the annual plant performance, levelized cost of electricity (LEC) with different solar multiples are determined and compared. Therefore an optimum solar field size, i.e. solar multiple, which gives the minimum LEC, for the ISCC plant could be obtained.

PerformanceAnalysis of Integrated Solar Combined Cycle Power Plant for Dhahran, Saudi Arabia

Saudi Arabia is blessed with abundant solar energywhichcan be use to meet its ever increasing power requirement. In this regard, the energy analysis and plant performance of integrated solar combined cycle (ISCC) plant with direct steam generation (DSG) was carried out for Dhahran, Saudi Arabia using four representative months of March, June, September and December. The plant consists of 180MW conventional gas turbine plant and two steam turbines of 80MW and 60MW powered by the solar field and gas turbine exhaust. With high insolation during the summer month of June the plant can achieve up to 25% of solar fraction with ISCC plant efficiency of 45% as compared to gas turbine base of 38%.This can however be improved by increasing the number of collectors or/and the use of auxiliary heater .

A comparative study between parabolic trough and solar tower technologies in Solar Rankine Cycle and Integrated Solar Combined Cycle plants

Simulations were carried out to predict the performance of a Solar Rankine Cycle (SRC) and an Integrated Solar Combined Cycle (ISCC) when combined with two different solar field configurations based on parabolic trough and power tower systems. For the selected cases, yearly plant performance was computed under real operating conditions on a one hour basis. A computing procedure was developed by integrating two commercial softwares with in-house computer code. Thermodynamic performance was featured for every plant configuration both at nominal and part load conditions. A single reheat regenerative Rankine cycle was chosen for the SRC plant whereas a commercial gas turbine, i.e. Siemens SGT-800, with a dual pressure heat recovery steam generator (HRSG) was assumed for the ISCC plant. As far as the heat transfer fluid (HTF) is concerned, molten salt was chosen to transfer heat to the water loop in the SRC. Synthetic oil was considered in the ISCC plant. Plants were assumed to be located in a Southern Spain site.The comparative analysis was mainly focused on the influence of CSP technology on global solar energy conversion efficiency of both SRC and ISCC plants. Special attention was devoted to assess trough collectors (PTCs) against the solar tower (ST) system in terms of intercepted radiation and thermal power sent to the power block. The ISCC coupled with a ST was found to assure the highest annual solar-to-electric efficiency of 21.8%. This is the result of both higher collection efficiency of ST compared to PTCs and higher conversion efficiency of solar energy introduced into the combined cycle, as compared to SRC.

Can Hybrid Solar-Fossil Power Plants Mitigate CO2 at Lower Cost than PV or CSP?

Fifteen of the United States and several nations require a portion of their electricity come from solar energy. We perform an engineering-economic analysis of hybridizing concentrating solar thermal power with fossil fuel in an Integrated Solar Combined Cycle (ISCC) generator. We construct a thermodynamic model of an ISCC plant in order to examine how much solar and fossil electricity is produced and how such a power plant would operate, given hourly solar resource data and hourly electricity prices. We find that the solar portion of an ISCC power plant has a lower levelized cost of electricity than stand-alone solar power plants given strong solar resource in the US southwest and market conditions that allow the capacity factor of the solar portion of the power plant to be above 21%. From a local government perspective, current federal subsidies distort the levelized cost of electricity such that photovoltaic electricity is slightly less expensive than the solar electricity produced by the ISCC. However, if the cost of variability and additional transmission lines needed for stand-alone solar power plants are taken into account, the solar portion of an ISCC power plant may be more cost-effective.